What prevents Pink Rozay from turning pink?

Hey mate, its mostly in the genetic. You can enhance the colorisation through swings or extreme values in temperature, ph or light. But that wont be good for your plant and when the genetic component for colorisation is completly missing in your plant you cant do anything sadly to make it color. Its just not possible sometimes. Maybe you will see slight colorisation in the maturing. Your plant looks more than nice anyway. Keep it up and Happy Growing!👌

It's a name, not a guarantee.

Hello jen_zee, The cause is genetics. Not every purle or red strain will turn purle. Mostly the breeder does advertise it as for example 80% from this strain will turn purple. I did grow a red strain once from Sweet Seeds. I did have a cabinet with 4 plants. 2 were red, 1 was more dark purple and 1 was green. Haha same seeds from the same package. But all 4 had the same sweet taste so I do not complain. Happy Growing Buddy! 💚

Some phenos just won't have the pink gene at all. Most colored phenos reakt to cold night temperatures around 18 degrees, so try to get your temp down if you can, but keep an eye on humidity.